Machine for cutting magnetic circuit lamine



Jan. 19, 1932. A. E R 1,841,909

MACHINE FOR CUTTING MAGNETIC CIRCUIT LAMINE vFiled April 12, 1929 4 Sheets-Sheet l INVENTOR. I 21 flfz azdom i ym wm A TTORNEY Jan. 19, 1932.

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Jan. 19, 1932.

o. A. PEARSON 1,841,909

MACHINE FOR CUTTING MAGNETIC CIRCUIT LAMINZE' Filed April 12, 1923 4 Sheets-Sheet 3 a I K mxwsl mm a k 5 INVENTOR.

aacarfliamofz/ ATTORNEY Patented Jan. 19, 1932 QNETQ TATES PATENT FFECE OSCAR A. PEARSON, OF OAK PARK, ILLINOIS, ASSIGNOR TO THORIDARSON ELECTRIC IMAN'UFACTURING COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS MACHINE FOR CUTTING MAGNETIC CIRCUIT LAMINZE Application filed April 12, 192-9. Serial I-Io. 354,568.

The invention relates to improvements in machines for cutting magnetic circuit laminae for use in the manufacture of electric'coils, the present invention constituting an improvement upon the machine illustrated and chine disclosed in the above-mentioned patent, thereby endowing said machine with improved and more extended capacities.

Another object of the present invention is to provide such a machine having the capacity of providing members for the formation of laminae for electric coils of various forms and designs adapted and arranged to cooperate with coils having difl'erent windings.

Another object of the invention is to provide a machine of the class indicated which is of simple construction and capable of rapid operation, thereby endowing the same with capacity for large daily output.

Other objects will appear hereinafter.

The invention consists in the combinations and arrangements of parts hereinafter described and claimed.

The invention will be best understood by reference to the accompanying drawings, in

39 which- Fig. 1 is a vertical section of the operative parts of a machine embodying the invention, showing only such portions of the cooperating punch press members as are necessary to 5 illustrate the cooperation of my improvements therewith;

Fi 2, a similar section showing the operative parts in different positions;

Fig. 3, a face view of one of the die membars of the machine;

Fig. 4, a face view of the other die member of the machine:

5, a partial section taken substantially on line 55 of Fig. 1;

Fig. 9, a diagrammatic face view illustrating the end of the strip of metal operated upon by the machine at the end of the first step in initiating the operation of the machine;

10, a similar view showing the condition of the end of the strip of metal at the end of the second step in initiating the operation of the machine;

Fig. 11, a view showing the condition of the end of the strip at the end of the final step in initiating the operation of the machine, and at the end of each succeeding normal operation thereafter'so long as the same strip is being continuously supplied; 1

Fig. 12, a view of one of two E-shaped plates formed by the normal operation of the machine;

Fig. 13, a view of the other of the-two E- shaped plates, shown in conjunction with the cooperating bar punching, the two constituting a complete laminae formed by the machine;

Fig. 14, a view showing two bars or punchings removed from the strip of metal in the second step in initiating the operation of the machine;

Fig. 15, a transverse section of a completed coil provided with laminae formed on the machine, said section being taken substantially on line 15 of Fig. 16;

Fig. 16, a section taken substantially on line 1616 of Fig. 17; and

Fig. 17, a side view corresponding with Fig. 16.

In the manufacture of magnet coils for various uses in the electric art it is common practice to employ thin iron or metal plates or laminations having portions to constitute the core of the coil and other portions to encompass the coil. For these purposes the plates or laminations are ordinarily stamped out of sheet metal or sheet metal strips, in the general shape of an E, with a central core member and two encompassing arms. In assembling the laminations it is necessary, or at least greatly desirable to complete a closed magnetic circuit of each lamination between the free ends of the central core portion and the two arm portions thereof. This is provide the continuous end portion of the E plate, and also the outer edge of the associciated bar or punching, with a notch, the several notches of the assembled structure at opposite sides thereof being aligned, to receive suitable clamping bolts which serve to hold the assemblyof laminations and bars securely in place, it being understood that the E. plates or laminations and their associated bars or punchings are disposed in relatively oppositely presenting directions.

In the manufacture of laminations and associated bars-and punchings it is very important to secure absolute symmetry and uniformity in shape and size of these members in order to secure and maintain uniform electrio and magnetic quality and characteristics in the magnet coils made therefrom. It is alsoimportant and highly desirable to produce the lamination members rapidly and economically and with the least possible waste of material.

My present invention is directed towards a machine for cutting or stamping out strips of sheet metal the laminations and associated bars or punchings of the character referred to, the special object in view being the provision of such a machine which is simple, efficient and speedy in operation, whereby the laminations and associated bars or punchings are-rapidly and econimically produced in absolutely symmetrical size and shape, andhaving'the desired notches to receive the securing bolts by. which they are efficiently and securely held when assembled into a complete magnet coil structure.

The preferred form of construction, as illustrated in the drawings, comprises a suit able punch press such as is employed in the machine of said prior patent and involving a reciprocating plunger or ram guided in suitable ways. on the frame 21; of the punch press and operated. from any suitable source of power. The ram 20 carries a punch holder 22 and a punch plate 23, as indicated, the latter carrying a punch member 24 arranged on the longitudinal medial line of the die. Cooperating with the reciprocating punch plate is a stationary die plate 25 mounted on the frame of the punch press andcarrying on its face adie plate 26, as shown. A combined stripper and guide plate 27 is arranged over the die plate26 to cooperate therewith. The stripper plate 27 is provided with an enlarged oblong opening'28-"to permit of the free passage of the punch member 24, which in this instance is of vertically elongated or oblong shape and of a size to pass freely through the opening 28. The die plates 26 and 25 are provided with cooperating die openings 29 and 30 to cooperate with and receive the punch member 24, as will be readily understood.

A spring-held inwardly slidable stop bar 32 is mounted, as indicated in Figs. 4 and 7, between the plates 26 and 27, said stop bar being provided at its outer end with an outwardly turned handle 33 for convenience of manipulation by the operator of the machine. The stop bar 32 is normally held in outward or inoperative position by means of a spring arm 34,.and a stop pin 35 projects through a slot 36 in said bar to limit the movements thereof. The stop bar 32 is operated by being depresesd or pushed inwardly by the operator of the machine so that the inner upper edge of the stop bar rests in the path of the advancing end of the strip of metal 37 when inserted in the machine by the operator to be op erated on by the machine. The upper edge of thestop bar 32 is so positioned relative to the punch member24 that said punch member will form a hole 39 in the strip 37, as indicated in Figs. 9, 10 and 11. It will be noted that, upon insertion of the strip 37 in the machine to rest upon the stop bar 32 for the initial operation of the machine, the hole 39 is formed centrally at the forward or advancing end of the strip when first inserted so as to constitute anotch in the forward end 40 of the strip. As shown, the forward edge 40 of. the strip may sometimes be somewhat irregular in form, (to be trimmed off in the subsequent operations) and for this reason the stop 32 is positioned slightly in advance or below the normal true edge when trimmedofli, as indicated by the dotted line 37' for the purpose to' be hereinafter explained.

The members thus far described constitute means to accomplish what I term the first step in initiating the operation of the machine, serving simply to form the opening or partial opening 39 in the strip 37 when said strip is first inserted by the operator for its forward end to rest against the stop 32, which is manually depressed into supporting position by the operator for the purpose. Upon release of the stop 32 by the operator, the spring arm 34 automatically withdraws the same,leaving the passageway free for the further endwise advance of the strip, which is thereupon done by the operator until the notch 39 engages a stop pin 41 positioned further down in the machine and at the end of what is termed the second step in the initiation of the operation thereof. The stop pin 41 is carried by the inner end of a lever 42 fulcrumed on the pin 43 and having a lateral projecting handle portion 44 and normally held in retracted or inoperative post-ion by means of a spring arm 45, as best shown in Figs. 4

and 8. The arrangement is such that the stop pin 41 will normally be held in retracted or inoperative position by means of the spring arm 45 or can be set by the operator to engage the notch 39, as indicated in Fig. 10, and stop and position the strip for what I term the second initiating step of the operation of the machine.

For this second step in initiating the operation of the machine, the punch plate 23 is proviced with two vertically elongated, symmetrically positioned punch or male die members i cooperating with similar slots 47 in the stripper plate 27 and with similar female die openings 48 in the die plates 26 and 25' and whereby, upon operation of the punch press, bars or strips 49 will be punched from the strip 37 to form parallel equally spaced symmetrical slots 49' in the said strip.

The punch members 46 are provided with notches 46 in their outer sides, and the die openings 48 are provided with corresponding projections 48 on their outer sides whereby notches L9 are formed in the outer edges of the removed bars 49, as will be readily understood and for a purpose which will presently appear. This operation leaves corresponding projections in the edges of the spaces from which the bars have been removed. These projections are trimmed off in the subsequent operation of the machine. Cooperating with the openings 48 is a supporting tray 50 carrying afriction block 51 slida-ble therein and having lateral friction springs 52 so that when the bars 49 are thus removed from the strip 37, they are delivered into the tray 50 by the normal operation of the machine, as will be readily understood.

The last step in initiating the normal operation of the machine is substantially the same as the last stage of initiating operation disclosed in the abovementioned prior pat ent to Thordarson. To this end, the punch plate 23 also carries two punch or male die members 53 arranged immediately below and in longitudinal alignment with the punch dies 16, as best shown in Fig. 8. As shown, these punch members 53 are somewhat larger than the punch members 46 and are arranged and adapted to trim off the projections formed in punching the notches 49', and enlarge the openings 49 in the strip 37, thereby forn'iing enlarged openings 54 in said strip. To accomplish this, the punch members 53 cooperate with die openings 53 in the die plate 26, as shown, and wnereby the openings 49 will be enlargeu and trimmed to form the openings 54, as will be readily understood.

The punch plate 23 also carries another punch or male die member 55 cooperating with a die opening 56 in the die plates 26 and 25. The upper edge 55 of the die member 55 cooperates with the lower edge 56 of the die plate 26 to trim 05 the forward end of strip 37, in initially inserting the strip into the machine to form the transverse cut or trim 37' in the strip 37 at each subsequent normal operation of the punch press.

7 Another punch or male die member 57 is arranged at the lower end of the die plate 26 cooperating with the die opening 57 in the plate 22. An accurate permanent stop 57 is arranged on the plate 25 at the extreme lower end of the plate 26 adapted and arranged to form a stop for the trimmed edge 37 of the inserted plate and accurately position' the strip in the machine for the nor mal operations thereof. The lower edge 58 of the diemember 55 cooperates with the upper edge 59 of the die member 57 to form a transverse cut 60 extending exactly through the longitudinal centers of the slots or openings 54. This forms the end of the strip; into two identical E-shaped plates 61 and 62, each provided with a central bar or projection 61 and 62, as shown in Figs. 11, 12, 13 and 15.

The plates 61 pass one way through the opening 56 into a tray 63 containing a friction block 64, and the plates 62 pass the other way through the opening 57 and into an opening 65 in the head 20 against the resistance of a block 66, as will be readily understood.

Stop bars 67 are also provided on the die plate 22 to cooperate with the stop member 57 passing on opposite sides thereof and serving as supports for the plates 62 as they are fed through the opening 57. The plate 22 is also provided with side arms 68 carryspring-held catches 69 to prevent retraction of the plates 62 from the opening 57 in substantially the same manner and having the same function as is performed in the Thordarson patent. By this arrangement, a machine is produced which will operate at high speed and great accuracy to produce the plates 61 and 62 and the bars 49 for the formation of laminae for electrical coils. coil is illustrated in Figs. 15, 16 and 17.

In commencing operations on the metal strip 37, immediately after the completion of the second stage of operations outlined above, the strip 37 is dropped downwardly sufficiently and the stop 41 engaged with the second hole 39 punched by the punch member 24, and the punch press operated with the strip in this position in order that the lower end 87 will be accurately trimmed with reference to the openings already formed so that, when the strip is fully inserted in the machine with the lower end 37 resting upon the stop 57", all parts will register properly with the various die members. Thereafter the machine is in condition to be operated normally, the intermediate or initiating operations being no longer necessary, and the strip is advanced after each succeeding normal operation of the punch press until the forward end at l Such a rests upon the stop 57", as will be readily understood.

As will be noted, the magnetic circuit for the coil is formed by assembling the plates and bars as shown. To this end, the plates 61 and 62 may be inserted in the coil from the side. the central bars 61 and 62' passing centrally into the bore of the coil. Associated with each plate is a bar 49, each plate and bar thus constituting a complete laminus of the coil. lVhen' the magnetic circuit has thus been completely built up, the cover plates 72 are then applied and the latter secured together by means of screw bolts 71 passing through the openings 39 and 49", as indicated.

To facilitate the operation of the machine, guide pins 73 are arranged on opposite sides of the opening 56 to accurately guide the strip to its proper position on the stop 57".

By this arrangement, a machine is produced which will produce the plates and parts for laminae, for use in the manufacture of electric coils, with great accuracy and uniformity, and with great rapidity and economy of production, and at the same time means are provided whereb v the openings or slots for the reception of the coil windings may be made in any desired size or shape thus permitting of corresponding variations in the windings of the coils.

\Vhile I have illustrated and described the preferred form of construction for carrying my invention into effect, this is capable of variation and modification without departing from the spirit of the invention. I therefore do not desire to be limited to the precise details disclosed but desire to avail myself of such variations and modifications as fall within the scope of the appended claims,

I claim:

1. A machine of the class described comprising in combination a punch press having cooperating male and female die members arranged to operate on a strip of metal in successive stages, one stage comprising die members adapted and arranged to punch openings to remove two parallel longitudinal bars of desired shape, thereby forming two corresponding slots, and a later operating stage comprising die members adapted and arranged to enlarge said slots, and a still later operating stage comprising die members adapted to transversely sever said strip centrally through said slots.

2. A machine for forming transformer laminae comprising a punch press having cooperating male and female die members arranged to operate on a strip of metal in successive stages, one stage comprising die members adapted and arranged to punch a notch centrally in the entry edge of the strip; a later operating stage comprising die members adapted and arranged to punch an opening; a later operating stage comprising die members adapted and arranged to enlarge said opening, and a still later stage comprising means for cutting the strip across the opening to produce a lamina.

3. A machine for forming transformer laminae comprising in combination a punch press having cooperating male and female die members arranged to operate on a strip of metal in successive stages, one stage comprising die members adapted and arranged to punch a notch centrally in the entry edge of the strip; a later operating stage comprising die members adapted and arranged to punch openings to remove two parallel longitudinal bars, thereby forming two corresponding slots; alater operating stage comprising die members adapted and arranged to enlarge said slots, and a still later stage comprising means for cutting the strip across the slots to form a lamina.

4. A machine of the class described comprising a punch press having cooperating male and female die members arranged to operate on a strip of metal in successive stages, one stage comprising die members adapted and arranged to punch a notch centrally in the entry edge of the strip; a later operating stage comprising die members adapted and arranged to punch an openin and a later operating stage comprising die members adapted and arranged to enlarge said opening, and a. final operating stage comprising die members adapted and arranged to transversely sever said strip centrally through said opening.

5. A machine of the class descriled comprising in combination a punch press having cooperating male an d female die members arranged to operate on a strip of metal in successive stages. one stage comprising die members adapted and arranged to punch a notch centrally in the entry edge of the strip: a later operating stage comprising die members adapted and arrangedto punch openings to remove two parallel longitudinal bars, thereby forming two corresponding slots; and a later operating stage comprising die members adapted and arranged to enlarge said slots, and a final operating comprising die members adapted and arranged to transversely sever said strip centrally through said slots.

6. A machine of the class described comprising in combination a punch press having cooperating simultaneously act ng male and female die members arranged to operate on a strip of metal in successive stages, the first stage comprising die members adapted. and arranged to punch a hole located centrally on the dividing line between the first and second stages. the second stage comprising die members arranged to remove two longitudinal bars of desired shape to form two longitudinal parallel slots. and the third stage comprising cutting members arranged to enlarge said slots and out said strip transversely through said first-mentioned hole and also transversely through said slots; a settable stop arranged to engage the end of said strip to position the same for said first stage, said stop being set far enough in advance to cause a small portion of said strip to protrude over into said second stage so as to be accurately trimmed in a later stage; a settable stop arranged to engage said first-mentioned hole to position said strip for said second stage; and a permanent stop for said strip arranged to engage the end thereof to position the same properly for all stages.

7. A machine or" the class described comprising in combination a punch press having cooperating simultaneously acting male and female die members arranged to operate on a strip of metal in successive stages, the first stage comprising die members adapted and arranged to punch a hole located on the longitudinal medial line of the strip and on the dividing line between the first and second stages, the second stage comprising die members arranged to remove two longitudinal bars having notches in their sides to form two longitudinal parallel slots, and the third stage comprising cutting members arranged to enlarge said slots and out said strip transversely through said first-mentioned hole and also transversely through said slots; a settable stop arranged to engage the end of said strip to position the same for said first stage, said stop being set far enough in advance to cause a small portion of said strip to protrude over into said second stage so as to be accurately trimmed in a later stage; a settable stop arranged to engage said firstmentioned hole to position said strip for said second stage; and a permanent stop for said strip arranged to engage the end thereof to position the same properly for all stages.

8. A machine for forming transformer laminae having in combination a punch press and cooperating male and female die members arranged, in the normal operation of the machine, to act simultaneously upon a strip of metal at relatively difierent points in its length, one set of die members operating at each stroke to punch an opening in the strip, another set operating on the succeeding stroke to enlarge said opening, and another set operating to sever the strips into proper lengths across the opening.

9. A machine for forming the transformer laminae having in combination a punch press and sets of cooperating male and female dies disposed in sequential order with respect to each other, to act upon a metal strip at relatively different points in its length and means to temporarily arrest the strip in successive steps of advancement while being introduced into the machine whereby one set of said dies operating at each stroke in the normal operation of the machine to punch out and remove formed therein.

In witness that I claim the foregoing as my invention, I allix my signature this 26th day of March, 1929.

OSCAR A. PEARSON. 

